Subminiature portable information processing apparatus, represented by personal digital assistants (PDAs), have been employed in various places due to the nature of the apparatus. In addition to the use of the portable information processing apparatus in vehicles such as trains and automobiles, if the apparatus is easily able to have access to information while standing in such a vehicle or while walking, it will be more convenient for use. However, in these circumstances, there are many cases where only one hand can be used.
The use for subminiature portable information processing apparatus that users can hold in one hand, as previously described, is mainly to access information, that is, information browsing. For example, the user selects a menu item as shown in FIG. 1A prior art and performs manipulation to display the contents of the selected menu item as shown in FIG. 1B prior art. In FIG. 1B, the display device of the portable information processing apparatus is small and all information within the menu cannot be displayed at a time, so there are cases where a scroll operation is performed. Such information browsing does not require that various information is input by an input means such as a keyboard, but, on the other hand, since there is the possibility that the user will employ this portable information processing apparatus while standing or walking, as described above, there is a need to design the manipulation interface so that the apparatus can be more easily manipulated than usual.
Now, if it is considered what requirements are imposed on the aforementioned interface, they will be as follows. That is, (1) To be able to perform digital movement from a current item to the next selectable item. The digital movement means that movement is performed from item to item. (2) To be able to perform two-dimensional movement from a current item to upper, lower, left, and right items. It is necessary to be able to move to all points on a display screen. (3) To be able to perform high-speed movement from a current item to a far item and scrolling. It is necessary to be able to perform continuous manipulation in an analog manner. (4) To be able to perform manipulation with one hand, including selection (invocation) of an item. It is necessary to be able to perform so-called click and double click. Particularly, if positioning cannot be easily made, double click cannot be performed. (5) To be able to perform manipulation even by feel. If operating circumstances are considered, a physical response to the manipulating hand will be an important element.
On the other hand, the following input devices are known as conventional input devices for portable information processing apparatus: (a) direct input by a pen and a touch pad; and (b) depressible digital dials. In the digital dial, if the dial is turned, a cursor will be moved in a one-dimensional direction, and when giving selection, the dial can be depressed. The dial is used for digital input. Each time the dial is turned a constant angle, a feedback is given to users and input of one unit is performed. A further device includes (c) a combination of cursor keys and a switch. They are cursor keys provided in a keyboard or a cross-shaped key provided in some of small game machines for indicating a direction, and a switch for selection. Yet another is (d) a combination of an analog input device (such as a track ball) and a switch.
The cursor key basically indicates movement which is performed one unit at a time. If the key continues to be pushed, the cursor will be moved continuously, but this merely means that digital inputs arise continuously. On the other hand, track balls or force sensible input devices, provided within the keyboard of a notebook computer produced by IBM Corporation, indicate continuous movement corresponding to the amount of rotation of the ball or the strength of a force applied to the force sensible input device, and therefore they give information processing apparatus an analog input.
The aforementioned input device (a) has the advantage that handwritten figures and characters can be directly input but has the disadvantage that both hands are needed even when it is employed for simple menu manipulation. Also, groping manipulation is difficult. The aforementioned input device (b) makes groping manipulation by one hand possible, but it requires mode switching, for example, when moving menu items right and left, because the device gives a one-dimensional input. The aforementioned input device (c) gives a two-dimensional input and therefore does not cause a problem such as (b). However, since an additional switch generally is needed for item selection, one-hand manipulation becomes difficult. In addition, in the input devices (b) and (c), high-speed movement between far items is not easy. The aforementioned input device (d) can easily perform high-speed movement because it gives a two-dimensional analog input, but it requires an additional switch for item selection, as in the case of (c). In addition, digital movement to an adjacent item and groping manipulation are difficult. Thus, it is found that any of these input devices does not completely meet the aforementioned 5 requirements. FIG. 23 shows whether or not each of the aforementioned input methods meets the five requirements. In FIG. 23, the mark ".largecircle." means that an input method meets a requirement, the mark ".DELTA." means that an input method has difficulty slightly but can deal with, and the mark "x" means that an input method does not meet a requirement.
In Japanese Published Unexamined Patent Application No. 4-263308, by moving a manipulation knob left and right, back and forth, and up and down, a detecting sensor section outputs a signal about an X, Y, and Z direction in correspondence with the direction in which the manipulation knob is moved. Furthermore, by providing a rotary encoder which outputs a signal by rotating the manipulation knob, a joy stick can set a numerical value in each direction. This joy stick can indicate X, Y, and Z directions, but cannot set a numerical value by moving the manipulation knob in the direction. Therefore, the user cannot manipulate the joy stick by intuition. There is no description of an insensitive zone. Also, it is described that the input in the Z direction can be employed as a mere switch. For X and Y directions, there is no description of a method which makes the aforementioned analog and digital inputs possible.
Japanese Published Unexamined Patent Application No. 61-147326 discloses an input device having a structure where a lever is rotatable on its lower end in an arbitrary direction and a circular plate is fixed to the lever by insertion, and 4 tack switches are provided away from the outer circumference of the circular plate by a predetermined length so that the switches make a right angle with each other. This input device has a structure where the lever returns to its original position if the user's hold of the lever is released. Furthermore, for the Z-axis direction, information as to the manipulation of the lever can be obtained with a slide volume knob or a switch.
It is disclosed that the detection of the displacements in X-axis and Y-axis directions can employ not a tack switch but a displacement-electric quantity conversion element. This input unit is constructed so that the displacements in X-axis and Y-axis directions can be detected with 4 detectors making a right angle with each other. Therefore, in the case where it is desired that the lever is continuously varied in direction, that is, in the case where the lever is moved while both the direction from the X-axis direction to the Y-axis direction and the displacement in that direction remain indicated, there are cases where the continuous movement of the lever cannot be continuously detected, because no detector is provided between the X axis and the Y axis.
Japanese Published Unexamined Patent Application No. 2-188819 discloses that a mouse indicates horizontal movement and that if a specific mouse button is pushed, a predetermined item will be moved one unit at a time. In such a device, an analog input is indicated with the ball of the mouse and a digital input is performed with the button of the mouse. However, since a digital input cannot be indicated with the ball of the mouse which indicates position change, a predetermined item can be only moved one unit at a time. That is, movement of an item cannot be performed in an arbitrary direction. Also, this input device cannot be manipulated with one hand, because it employs a mouse.
Japanese Published Unexamined Patent Application No. 59-33539 discloses a device where, when the inclination of a joy stick is within a predetermined range, a marker on the display screen is moved in correspondence with the inclination and, when the inclination exceeds the predetermined range, the marker is repeatedly moved in the direction by a constant quantity at a time. It is described that this device has both a mode where movement of a marker is small and positioning is easy and a mode of moving a marker at high speed, but only the marker can be manipulated on display screen. Also, no description is made of manipulation in a Z-axis direction and an insensitive zone. Furthermore, this device has the disadvantage that manipulation will be difficult if the user does not view the display screen, because switching of modes is determined by the inclination of the joy stick.
Japanese Published Examined Patent Application No. 64-8846 discloses a device which continuously outputs a cursor-moving pulse when the inclination of a joy stick is greater than a predetermined angle for a period longer than a predetermined time. The device also outputs a single cursor-moving pulse when the inclination of the joy stick is greater than the predetermined angle for a period shorter than the predetermined time. Even in this device, what is manipulated in both modes is only a cursor. Also, there is no description of the manipulation in a Z-axis direction. Furthermore, this device has the disadvantage that manipulation will be difficult if the user does not view the display screen, because made switching is determined by the inclination of the joy stick and the time of the inclination.
Japanese Published Unexamined Patent Application No. 5-241502 discloses that scrolling of a display screen is performed with a joy stick. However, this publication does not disclose that the scroll operation and other different operations are combined and executed.
Note that an example of a pointing device provided on a keyboard is described in Japanese Published Unexamined Patent Application No. 7-302162. In this publication there is disclosed a device where force is applied to a stick provided on the keyboard in X-axis and Y-axis directions and where strain, produced in the stick by the force, is detected by a strain gauge, an electrostatic capacity detection sensor, a magnetic detection sensor, or a pressure sensitive detection sensor. In this device, no description is made of an input in a Z-axis direction, and only an analog input is possible. Also, a physical insensitive zone does not exist.
On the other hand, in IBM: Technical Disclosure Bulletin (TDB) (95-07, p 487), for a nearly similar structure, it is described that a pressure sensor is provided under a stick to detect a vertical input from the stick and that emulation is performed with a 3-button mouse along with two buttons normally provided. However, this publication, as with Japanese Published Unexamined Patent Application No. 7-302162, does not disclose that a digital input is performed only with the manipulation of the stick. Also, there is no description of a physical insensitive zone.